1. Field of the Invention
This invention relates to devices for the control of obesity, and, more particularly, to a surgically implantable adjustable band for encircling the stomach.
2. Prior Art
Several years ago, Kuzmak, et al. in U.S. Pat. 4,592,339, incorporated herein by reference, described a belt-like band for encircling the stomach to control morbid obesity. The band comprised substantially a belt which could be passed around the stomach in a circling position and then cinched tight in order to adjust the stoma opening within the stomach. Further improvements in the gastric band have included having an adjustable portion of the band comprising an inflatable member which permits the fine adjustment of the stoma opening after the size of the stoma is initially set by the band tightening procedure. The band tightening procedure normally involves the placement of a calibrating apparatus in the stomach to detect the stoma size. Once the apparatus is placed within the stomach the gastric band is cinched down tight until the stoma opening approximates the desired size. The band is fastened in position, usually by sutures, and the stoma opening finally adjusted by injecting a fluid into an inflatable member which is coextensive with a portion of the inner stomach-contacting surface of the band. The means for injecting the fluid into the inflatable member usually comprises a fill port located beneath the skin which can be accessed extracorporeally by transdermal injection. Thus, following implantation, the gastric band can be adjusted, within a narrow range, to enlarge or reduce the stoma as required.
One of the disadvantages of the prior art gastric bands is the difficulty in tensioning the band around the stomach to approximate the desired stoma. This is particularly difficult when the band is to be placed laparoscopically. When the band is placed laparoscopically, special instruments are required to tension the band prior to the fine adjustment of the stoma. Such instruments as are required to grasp the band and pull it into an encircling position around the stomach then cinch it tight, are difficult to manipulate through a laparoscopic canula. It would therefore be desirable to provide a band having an inflatable member thereon which can be easily fastened into an encircling position around the stomach and in which the final adjustment of the stoma opening can be regulated solely by the injection of fluid into the inflatable member.